Fluid releasing means for compressors and the like



YQUEM bill] JUNI Oct. 19, 1937. F. P. MCMAHON FLUID RELIEASING MEANS FOR COMPRESSORS AND THE LIKE Filed Aug. 26, 1935 a'nc @r @ma f Patented Oct. 19, 1937 UNITED `STATES man ont MUUNE PATENT CFFICE FLUID RELEASING MEANS FOR- COMPRES- SORS AND THELIKE Application August 26,

10 Claims.

My invention relatesin general to fluid dynamics and'more particularly to iluid ow devices, the invention havingv specific reference to a compressor particularly well adapted for use in refrigerating systems.

The invention has, ,for an important object, the provision of improved means for conducting compressedv fluid from the compressor while muffling or suppressing the noises of escaping medium.

Another important object is to provide iluid discharge means for a compressonfwhich is submerged in a bath of lubricant and hence likely to become floodedduring its inactive periods, said discharge means `being formed to promote the rapid removal. of the'lubricant from the compressor, upon starting of the same, withoutimparting undue Aor excessive strain upon theoperating parts of the device, while, at the same time, permitting discharge ofv such work medium as may be delivered through thecompresscr in compressed -condition during initial starting movement` without interfering with the lubricant ejecting operation.

Another important object is to provide a discharge manifold or muiller chamber comprising a sheet metal element" secured, to the frame ofthe compressor and forming a chamber into which fluid media, under pressure from the compressor, may be delivered substantially without disseminating exhaust noises.

Another important object is to provide discharge muilling means for a compressor comprising means forming anenclosed chamber, into Which'fluid media, compressed as a result of the operation of the compressor, may be delivered, said muier being adapted to suppress exhaust noises and including ,means for ejecting any liquid which may become entrapped in said chamber whereby to maintain the same inv purged liquid free condition during the operation .of the compressor; a further object being to form the ejector so as to purge the chamber rapidly of a relatively large quantity of liquid with which the same may becomeflooded when the compressor is inactive; and a Istillfurther objectbeing `to provide means permitting delivery of gases from the mufiler chamber during the purging operation.

Another object is to provide, in combination in a gas compressor, means'forming a muiiler chamber comprisingv a vsheet metal casing secured to the'frame of the compressor in position forming.

a chamber, into which gases may be delivered under pressuregas a result of the operation oi!v the compressor, said sheet metal element carry- 1935, Serial N0. 37,860

ing an ejector pipe having an end opening within the muiller chamber, preferably adjacent the bottom thereof,l and an end opening outwardly of said chamber whereby any liquid, trapped in the chamber, may be expelled through said pipe, the pipe serving to liberate compressed gases from the muilier chamberas long as the same is free of liquid and serving to eject liquid rapidly from the chamber when the same is ooded, the invention further contemplating the provision of a check valve on said sheet metal shell, the valve being normally closed to ensure delivery of the compressed gases through the ejector pipe but being adapted to open and release gases directly from the chamber when and if the ejector pipe isrlled with liquids when in operation to purge the chamber of liquid.

Numerous other objects, advantages, and inherent functions of the invention will be apparent from the kfollowing description, which, taken in connection with the accompanying drawing, discloses a preferred embodiment of the invention.

Referring tothe drawing:

Figure 1 is a vertical section through a sealed element comprising a compressor including a muiiier construction embodying my present invention` together with means for driving the compressor;

Figure 2 is a horizontal section taken through the muiiier chamber and the compressor substantially along the line 2-2 in Figure 1;

Figure 3 is a vertical section taken through the muiiler chamber substantially along the line 3--3 in Figure 1 and showing a preferred check valve construction;

Figure-4 is a similar vertical section illustrating a modied form of check valve; and

Figure 5 is a view of a modied check valve I6l.

To illustrate my invention, I have shown on the drawing a fluid-forcing device particularly adapted for use in a refrigerating system of. the evaporator-compression type wherein a suitable refrigerating medium, in, gaseous condition, is compressed, then liquefied, and finally evaporated for the absorption of heat, the gases evolved, by the evaporation of the refrigerating medium, being returned to the compressor for a repetition of the refrigerating cycle. It will be obvious, however, that the invention is not necessarily restricted to compressors or devices used in refrigerating systems. On the contrary, the invention includes features which may be incorporated to advantage in uid-dynamic devices generally.

I propose the features of. my present invention, however, more particularly for application in fluid-forcing means adapted for substantially noiseless, leak-proof operation over long periods of time without attention in order to provide a preferably motor driven compressor for use in domestic refrigerators, wherein the foregoing characteristics, particularly noiseless operation, are highly desirable.

The illustrated motor compressor mechanism comprises a sealed unit including fluiddynamic means comprising a compressor I3 and dynamo-electric means 5 drivingly connected with the compressor. The compressor and electric means are preferably sealingly enclosed in an hermetic housing I'I, which may be formed conveniently as a co-operating pair of sheet metal elements I9 and 2| having marginal flanges 23 and 25 secured together preferably by and between a pair of annular clamping rings 21 and 29 as by means of bolts 3| penetrating the flanges 23 and 25 and the ring 21 and threading into the ring 29. The casing I1 is or may be supported in any suitable fashion, as by means of legs 33 connected to the ring 29 and extending downwardly thereof in position to engage a support frame or base 35, on which the unit is mounted. The lower end of the leg 33 is preferably connected on the base as by means of a suitable mounting 31, preferably of the shookless type illustrated in the co-pending application of Mahlon W. Kenney and Arthur R. Constantine, Serial Number 714,447, filed March 7, 1934.

Thermotor I5 preferably comprises a stationary portion 39 carrying windings 4| and a movable portion or rotor 43, while the compressor I3 comprises a cylinder 45 and a piston 41 within the cylinder and forming therewith a compression or work space 49. The cylinder and piston are relatively movable to perform a fluid-forcing function upon a preferably gaseous work medium within said work space.

I prefer to form the cylinder as a stationary element while the piston is rotatable within the cylinder about an axis 5| eccentric with respect to the axis 53 of the cylinder.

All of the parts of the motor and compressor are preferably supported on a frame or spider 55, comprising an annular rim 51, a central hub 59, and arms 5I inter-connecting the hub and rim. The rim is formed with a seat adapted to receive the stationary element 39 of the motor, which is secured in place by holding studs 63 extending through the stator and threading into openings in the rim opposite the legs 6|.

The cylinder l5 comprises an open ended element, the inner bore of. which denes the outer surface of the compression space. One end of the element is secured to an 'end of the hub 59 in any suitable manner, preferably by means of studs 53 passing through a flanged portion 65 of the hub and threading in sockets formed in the end of the element 99. The opposite end of the cylinder l5 is closed by a cover 61 comprising a preferably circular disk secured on the end of the cylinder l5 by the studs 6|.

The piston comprises a cylindrical el-ement carried on a preferably integral axle 1|, which is journalled in the hub 59 in position such that the axis 5| of the piston is eccentric with respect to the axis 53 of the cylinder, and the parts are arranged to provide running contact between the surface of the piston and the inner bore of the cylinder along a line 13 lying in a plane common to the axes 5| and 53 whereby the Work space 49 is of crescent-shaped, cross-sectional configuration with the arms of the crescent extending on opposite sides of the line of contact 13.

The cylinder is formed with a plurality of openings 15, comprising discharge ports communicating with one arm or horn of the Work space, and the cylinder element also is formed with a slot 11 opening upon the other arm of the work space on the side of the contact line 13 opposite from the ports 15. The walls of the cylinder are formed with a channel or duct 19l extending from the slot 11 to the end of the element, which is secured to the hubl 59. One of the legs 4| of the frame is enlarged as at 8|, said enlargement containing a duct 83 opening at one end upon the surface of the hub 65 in communication with the channel 19, the duct 83, at its other end, opening outwardly of the cylinder element.

The motor and compressor are supported within the shell by projections formed on the flanged portion 65 of the hub and extending to and resting on supports formed on the inner wall of the casing in any suitable fashion. In addition, a fitting 85 is mounted on the wall of the shell element 2|, at an opening 81 therein. The tting has a preferably threaded nipple extending through the opening and sealingly secured therein so that the fitting 05 forms a hanger attached on the housing and on which the enlargement 8| may be seated, the parts being preferably secured together by suitable fastening elements. The fitting 85 is formed withy an enlarged chamber 89, opening at its upper end upon the duct 83. The lower portions of the chamber 89 contain a frame carrying a strainer 9| and supporting an annular element 93 forming a seat for a disk valve 95. Above the element 93 is arranged a preferably she-et metal valve guard 9-1, held in place by means of a pin 99 carried by the frame and having an end projecting in position to engage the guard and prevent the same from shifting within the chamber 89. The threaded nipple of the seat 85 is formed with a duct |0| connecting with the chamber 89 and is adapted for attachment with conduit means |03, through which a work mediumV may be delivered through the duct |0| into the valve chamber, and thence into the duct 83, thence through the duct 19 to the inlet slot 11. Rotation of the piston, relative to the cylinder, in the direction shown by the arrow in Figure 2 of the drawing will cause the work medium to be compressed in the work space 49 and be delivered thence in compressed condition held in place by means of a fastening stud |09 extending through the end wall of the cup-shaped element and threading into a suitable opening I formed in the walls of the cylinder element. The housing |01 forms a receiving chamber ||3, into which the compressed work medium is delivered through the ports 15. The element |01 thus forms a muffler and is adapted to suppress noise generated as a result of the ejection of the Work medium under pressure through the outlets 15.

The shell |01 has a pipe I5 extending through an opening ||1 in the upper wall of the shell, the pipe being sealed in the opening, as at I I9, and having a lower end |2| extending adjacent the bottom of the muffler chamber and an outletl end |23 opening into the sealed casing |1, so that gases, delivered into the chamber through the port 15, may escape thence, as a continuous gas stream, through the pipe ||5 and into the cas'- ing |1.

During the operation of the compressor, the casing becomes loaded with the work medium at the delivery pressure of the compressor, the gases eventually escaping from the casing through an outlet nozzle |25, comprising a channelled fitting sealed on the casing element |9 at an opening therein. The fitting |25 is preferably formed with screw threads |21 to facilitate connection with suitable conduit means, through which delivery of the compressed medium may be made to any desired place of use.

The shaft 1| has an end extending upwardly of the hub 59 and formed to receive and support the rotor 43 of the motor, which is attached on the upper end of the shaft in any suitable fashion, said rotor being carried on a frame |29 comprising a tapered sleeve |3| adapted to fit upon the correspondingly tapered projecting end of the shaft, said sleeve being held on said shaft by means of a washer |33 and a holding stud |35 threading into the end of the shaft.

The shaft 65 is preferably formed with a pair of spaced bearing portions |31 and is received in a sleeve-like bushing |39, having a preferably helical groove cut in its inner surface for the purpose of aiding in lubrication of the shaft bearings. The outer surface of the sleeve |39 is preferably formed with a plurality of parallel grooves |4| disposed at one side of and at the lower end of the sleeve. The sleeve l 39 is rmly tted into the. hub 59, which is provided interiorly with an annular groove |43, with which the grooves |4| communicate and the annular groove |43 is connected with the outer surface of the hub 59 by means of a duct |45.

Any suitable means may be provided for lubricating the operating parts of the compressor and particularly the shaft bearings. I prefer, however, to accomplish lubrication by enclosing a quantity of a suitable lubricating medium within the housing 1. To this end, the housing may contain a quantity of preferably liquid lubricating medium |41, which gathers in a pool or reservoir at the bottom of the casing element 2|, the lubricant reaching an approximate level indicated by the line |49 in Figure 1. The compressor is thus partially submerged in the lubricant pool. The plate 61 is provided with an opening I5 through which lubricant from the pool may enter the cylinder of the compressor and I may provide a screen or strainer |53 on the disk or plate 61 for the purpose of ltering the lubricant before the same enters the inlet |5|.

The piston of the compressor comprises a cylindrical element provided with a plurality of channels |55 extending parallel and in spaced relationship with respect to the piston axis. Slots I 51 are formed in the body of the piston radially of said channels, the slots, as well as the channels, extending from end to end of the piston element.

A fluid-forcing vane or blade |59 is arranged in each of the slots, the blades being long enough to bear at their opposite ends on the facing surfaces of the cover 61 and the hub 59. 'Ihe blades also are slidable in the slots, so that their outer edges may bear upon the inner surface of the cylinder at all times during the rotation of the piston therein. When the driving motor is energized, it will drive the piston within the cylinder in a direction causing the blades to sweep across vw..."- wuu uuvv| the crescent-shaped work space in the direction shown by the arrow in Figure 2 of the drawing in order tocause compression of a work medium entering the chamber at the inlet 11 and delivery of the compressed medium through the outlet openings 15. The blades will normally be urged outwardly in the slots |51 by centrifugal action during rotation of the piston. 'Ihe blades, however, will be reciprocated in the slots during rotation of the piston due to the fact that their outer edges ride upon the inner surface of the cylinder.

The reciprocation of the blades in the slots provides a pumping action, which may be utilized to draw the lubricating medium from the pool or reservoir and deliver the same under pressure to the shaft bearing. To this end, the inlet port |5| is located in the cover 61 in a position, with respect to the eccentric axis of the piston and cylinder, such that the ends of the channels |55 are each successively placed in communication with the opening 5| while the corresponding blade of said channel is moving outwardly in its associated slot. During the movement of the piston, when a blade is returned into its slot, the channel |85 is out of communication with said inlet. Consequently, oil will be drawn successively into the channels |55 through the oil inlet and will be compressed in the channels during the rotation of the piston.' The. ends of the channels, facing the hub, however, are successively placed in communication with the grooves |4| during the piston movement which causes the blades to travel inwardly in their slots. Consequently, the lubricant, drawn into and compressed in said channels |55, may be delivered to the. grooves |4| and also to the lower end of the shaft bearing. Some of the lubricating medium may penetrate the shaft bearing in order to lubricate the same, such oil being carried through the. helically grooved bearing, by the rotation of the shaft therein, the lubricant escaping at the upper end of the bearing and being returned by gravity to the lubricant reservoir. The rest of the lubricant, which is delivered in the grooves |4|, may escape into the annular chamber |43, thence through the duct |45 and return by gravity to the lubricant reservoir. Such lubricant serves to cool the main bearing. A part of the lubricant may also escape from the channels |55 through the blade slots on opposite sides of the reciprocating blades in order to provide adequate lubrication for the same. Such lubricating medium, of course, enters the work space and will be expelled together with the gaseous work medium into the mufller chamber 19 and will be carried thence through the outlet pipe I5 into the housing |1, whence it may return to the reservoir |41.

If, for any reason, the compressor remains idle for an appreciable length of time, lubricant from the reservoir or pool, in which the compressor is partially submerged, may seep into the compressor and flood the same and the chamber |3 to the level of the oil in the reservoir. Under such circumstances, it is desirable to provide for the rapid ejection of the usually liquid lubricant whenever the compressor is started in operation, since it will be obvious that the compressor cannot efficiently operate on a gaseous work medium as long as it is flooded with the liquid lubricant. At the same time, I desire to provide means for releasing, into the casing, any compressed gases delivered in the chamber |3 during the lubricantV purging operation. To this end, the upper portion of the shell |01 is provided with a check valve IBI of any suitable or preferred construction and adapted to open and release the entrapped gases as long as the lower end of the pipe H5 is submerged in the liquid lubricant.

The top of the shell |01 is preferably formed with an opening |63 forming a seat |65 for a ball valve |61, which is held in place by a suitable retaining element |69 carried by the shell |01. As soon as the compressor is started in operation, entrapped oil will be forced rapidly through the pipe H5, due to the development of pressure within the chamber H3. The excess pressure thus developed in the chamber will also open the check valve as by raising the ball from its seat, thus permitting any gases, that are or may be delivered into and entrapped in the chamber, to escape directly into the housing I1. Since the pipe H5 extends substantially to the bottom of the chamber H3, the chamber H3 may be substantially and rapidly cleared of oil while the check valve permits the compressed gases to enter the` housing I1, while the chamber is being purged of the lubricating medium by expulsion of the same through the pipe I I5. The oil thus ejected, of course, returns immediately to the reservoir. After the muler chamber has thus been completely purged of the lubricant, the pipe H5 may carry substantially all of the compressed gases and deliver the same into the housing I1 and the check valve, under such conditions, remains closed.

In Figure 5 of the drawing, I have illustrated a modified check valve IGI, wherein the retaining element |69 is eliminated and, for the ball valve |61, is substituted a valve element |68 having a head |10 adapted to engage the seat |65 and a shank |12 adapted to extend through the opening |63 and carrying a cylindrical weight |14 within the chamber H3, said weight |14 comprising a cylindrical block having a channel adapted to receive the shank I 12 and adapted to be secured on the shank by means of a cotter pin |16 mounted in a perforation |18 in the end of the shank below the weight. I prefer also to provide a washer |80, preferably of the type having slotted internal teeth |82, upon the shank |12 between the weight and the head |10. The weight |14 normally maintains the head in closed position on the seat |65, thus preventing escape of the compressed gaseous medium as long as the pipe H5 remains open and available for carrying the gases. When the pipe becomes lled with liquid, the gases within the chamber H3 may reach a degree of compression permitting them to raise the valve from its seat against the gravity influence of the weight |14 and thus escape through the opening |63. The function of the washer is to prevent the weight from becoming sealed against the walls defining the opening |83 and thus impede egress of the gases.

Any suitable means may, of course be provided for powering the motor I5, but I prefer to utilize conductors connected with the windings 4I and passing out of the casing I1 through sealed bushings I1I carried by the casing portion I9, said conductors being connected with a suitable electrical power source externally of the casing.

As heretofore mentioned, the device of my present invention is especially well suited for use in refrigerating systems, and I particularly contemplate the application of the present invention in domestic refrigerators embodying compressionexpansion systems utilizing, as a refrigerant, amedium which will not dissolve in the liquid lubricant. With such a refrigerant, there is substantially no problem involved in separating the gaseous refrigerating medium from the liquid lubricant. I have found that dichloromethane is a suitable refrigerating medium, which, when in gaseous condition, is substantially insoluble in mineral oils of the character which I prefer to use as a lubricating agent in apparatus of the character mentioned.

The lubricant, upon ejection from the operating parts of the compressor and from the muffler chamber, settles to the bottom of the casing, while the compressed gaseous refrigerant escapes through the nozzle at the top of the casing and may be delivered thence, in succession, to a condenser, where the refrigerant is liquefied by cooling, an evaporator, where the liquid refrigerant may gasify and absorb heat, the gasied rerigerant being returned through the conduit |03 to the suction side of the compressor.

It is thought that the invention and numerous of its attendant advantages will be understood from the foregoing description and it is obvious that numerous changes may be made in the form, construction, and arrangement of the several parts of the illustrated apparatus without departing from the spirit or scope of my invention or sacrificing any of its attendant advantages, the forms herein described being merely for the purpose of illustrating the invention.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is as follows:

1. A muler device for use in combination with a uid dynamic device having an inlet and an outlet, said muiiler device comprising sheet metal means mounted on said dynamic device in posi tion to form a receiving chamber, into which a work medium may be delivered through said outlet, ejector means forming a conduit opening inwardly as well as outwardly of said receiving chamber whereby to deliver the work medium from said chamber, said ejector means comprising a pipe extending through and sealed in an opening in said sheet metal means and having an end disposed adjacent the bottom of said chamber whereby any liquid, entrapped in said chamber, may be ejected through said pipe.

2. A muler device for use in combination with a fluid dynamic device having an inlet and an outlet, said mulller device comprising sheet metal means co-operatively associated with said dynamic device and forming a receiving chamber for a work medium delivered through said outlet, means forming an ejector conduit opening within the chamber near the bottom thereof and also outwardly of said chamber whereby any liq. uid entrapped in the chamber may be ejected through said conduit, and a normally closed check valve in the upper portions of said chamber, said valve being adapted to open to release gases from the chamber while liquid is being ejected through said conduit.

3. A muffler device for use in combination with a fluid dynamic device having an inlet and an outlet, said mufller device comprising sheet metal means co-operatively associated with said dynamic device and forming a receiving chamber for a work medium delivered through said outlet, means forming an ejector conduit opening within the chamber near the bottom thereof and also outwardly of said chamber whereby any liquid entrapped in the chamber may be ejected through said conduit, and a normally closed check valve in the upper portions of said chamber, said valve being adapted to ouen to release gases from the CFI sues

chamber while liquid is being ejected through said conduit, said check valve remaining closed when the conduit is free of liquid and able to conduct gases from the chamber.

4. Fluid release means for use in combination with a fluid dynamic device having an inlet and an outlet, means forming a muiiler chamber attachable on said dynamic device in position communicating with said outlet and providing for the noiseless release of a iiuid medium delivered through said outlet into said chamber, and a check valve formed in the walls of said chamber for releasing a work medium under the control of the check valve.

5. Fluid release means for use in combination with a fluid dynamic device having an inlet and an outlet, means forming a muiiier chamber attachable on said dynamic device in position communicating with said outlet and providing for the noiseless release of a iluid medium delivered through said outlet into said chamber, a check valve formed in the walls of said chamber for releasing a work medium under the control of the check valve, said check valve comprising a valve element normally urged to engage a seat provided by an opening in the walls of said chamber, and means to retain said valve element in position.

6. Fluid release means for use in combination with a iiuid dynamic device having an inlet and an outlet, means forming a muffler chamber attachable on said dynamic device in position communicating with said outlet and providing for the noiseless release of a fluid medium delivered through said outlet into said chamber, a check valve formed in the walls of said chamber for releasing a work medium under the control of the check valve, said valve comprising a spherical valve element normally engaging a seat defining an opening in the Walls of said chamber, and retaining means for securing the spherical valve element opposite said seat.

'7. Fluid release means for use in combination with a fluid dynamic device having an inlet and an outlet, means forming a muiiler chamber attachable on said dynamic device in position communicating with said outlet and providing for the noiseless release of a iluid medium delivered through said outlet into said chamber, a check valve formed in the walls of said chamber for releasing a work medium under the control of the check valve, said valve comprising a valve element normally urged by gravity to engage a seat defining an opening in the walls of said chamber,

EMCH UU and means to retain said element inoperative position opposite said seat.

8. Fluid release means for use in combination with a fluid dynamic device having an inlet and an outlet, means forming a muiiler chamber attachable on said dynamic device in position communicating with said outlet and providing for the noiseless release of a fluid medium delivered through said outlet into said chamber, a check valve formed in the walls of said chamber for releasing a Work medium under the control of the check valve, said valve comprising a valve element having a head adapted to engage a seat defining an opening in the Walls of said chamber and a shank extending through said opening and carrying a Weight whereby to normally urge the head toward seat-engaging position.

9. Fluid release means for use in combination with a fluid dynamic device having an inlet and an outlet, means forming a muiller chamber attachable on said dynamic device in position communicating with said outlet and providing for the noiseless release of a fluid medium delivered through said outlet into said chamber, a check valve formed in the walls of said chamber for releasing a work medium under the control of the check valve, said valve comprising an element comprising a shank and a head adapted to engage a seat defining an opening in the Walls of said chamber, said head extending on one side of the said Walls and the shank extending through the wall-opening, weighted means on said shank on the side of the wall opposite from the head whereby said weighted means is suspended Within said chamber so that the gravity eifect of said Weighted means serves to maintain the head in engagement with said seat.

10. Fluid release means for use in combination With a fluid dynamic device having an inlet and an outlet, means forming a muffler chamber attachable on said dynamic device in position communicating with said outlet and providing for the noiseless release of a fluid medium delivered through said outlet into said chamber, a check valve formed in the walls of said chamber for releasing a work medium under the control of the check valve, said check valve comprising a spherical ball normally engaging a seat defining an opening in the walls of said chamber, said ball being disposed outwardly of said chamber, and retaining means comprising a spoon-like portion mounted in spaced position opposite said seat and. adapted to retain the ball opposite said seat when the same is moved away from the same.

FRANCIS P. MCMAHON. 

